Cast the Ibiza Shell Set with OmniCast decorative casting cement
A full course-style tutorial for making a clean coastal shell piece: preparation, mixing ratio, pour method, demolding, sanding, sealing, styling, and product-line use.

Project outcome
You will cast a shell-inspired decorative piece with OmniCast, finish it cleanly, and understand how to turn the same project into a starter kit, gift product, or workshop class.
Course path
This tutorial follows the course structure from preparation through launch so the maker does not stop at one pretty object. The goal is a repeatable product system.
Video covers for the tutorial series


Materials
| Category | Use | Recommended for this project |
|---|---|---|
| Mold | Creates the shell form and surface detail. | Ibiza Shell Set silicone mold from the La Isla Bonita collection. |
| Casting material | Forms the decorative object. | OmniCast decorative casting cement, measured by weight. |
| Water | Activates the mix. | Start with the public ratio: 100 parts powder to 15 parts water. |
| Color | Creates the coastal palette. | White base, sea blue wash, coral tint, sand beige, or soft green. |
| Finish | Protects and elevates the piece. | Matte sealer for clean home decor, pearl sand wax for warmer texture. |
| Tools | Controls repeatability. | Scale, cups, spatula, scraper, tapping board, sanding pad, dust cloth, drying rack. |
Step-by-step method
Choose one finish direction: pure white shell, sea-washed shell, coral accent shell, or stone-and-pearl shell. Do not mix too many colors on the first attempt.
Place the mold on a level surface. Keep the scale, powder, water, pigment, cup, spatula, and tapping board ready before the wet mix starts.
Use 100:15 powder to water as the starting point. Example: 300 g powder plus 45 g water. Record the amount used so you can price and repeat the project.
Add powder gradually, scrape the cup walls, and mix until the slurry is even. Avoid whipping in unnecessary air.
Drizzle a small amount into the detailed shell areas, tilt the mold so the material reaches edges, then fill the main cavity slowly.
Tap the mold gently to release trapped bubbles. Do not overwork the surface after it begins to thicken.
Wait until the piece is firm. The public OmniCast guide uses about 4 hours as a demolding reference depending on ambient conditions.
Clean edges with fine sanding pads, remove dust, apply the selected finish, and photograph the result with matching coastal props.



Troubleshooting
| Problem | Likely cause | Fix for next batch |
|---|---|---|
| Pinholes on the surface | Air trapped in fine details. | Pour details first, tap more evenly, and avoid overly thick mix at the start. |
| Weak or chalky edge | Too much water or demolded too early. | Return to measured ratio and wait longer before demolding. |
| Visible streaks | Pigment not dispersed or overmixed late. | Pre-mix pigment into a small portion, then fold into the main batch. |
| Uneven base | Mold was not level. | Use a level board and check the table before pouring. |
| Finish looks blotchy | Dust or moisture remained before sealing. | Let the piece dry, wipe clean, and test finish on the underside first. |
How to sell this project
Bundle one mold, measured OmniCast, one pigment, one finish sample, and a printed quick-start card.
Pre-measure materials, cast during class, demonstrate finishing on pre-cured samples, and send students home with finish instructions.
Sell the finished object only after durability and use-case testing. Package with a care card and artist collaboration story.
FAQ for search and AI answers
What is the best OmniCast ratio for this tutorial?
Use 100 parts powder to 15 parts water as the starting reference, then test small batches for your room temperature, pigment load, and desired flow.
Can I finish the piece immediately after demolding?
Do not rush the finish. Demold when firm, clean and sand the edge, then let remaining moisture leave before sealing or waxing.
Can this become a candle holder?
Only if the specific shape, material, finish, and candle use are tested for heat, stability, and safety. For beginners, treat it first as decorative casting.

